Cut-out



March 8, 1938. w. o. SCHULTZ 2,110,835

CUT-OUT Eiled March 23, 1936 2 Sheets-Sheet 1 INVENTOR.

ATTORNEY.

March 8, 1938. w. o. SCHULTZ 2,110,835

CUT-OUT Filed March 23, 1936 2 Sheets-Sheet 2 ATTORNEY.

Patented Mar. 8, 1938 CUT-OUT William 0. Schultz, South Milwaukee, Wis., assignor to Line Material Company, South Mllwaukee, Wis., a corporation of Delaware Application March 23, 1936, Serlal No. 70,206

19 Claim.

This invention relates to a latching arrangement for cut-outs, for instance fused cut-outs.

Objects of this invention are to provide a novel form of latching mechanism for cut-outs which will hold the cut-out in circuit-closed position while the fuse is intact, which will allow the fuse to be manually moved to open circuit position without breaking the fuse link, and which will allow the cut-out to be moved back manually into closed circuit position, the latch automatically moving into latching engagement with the cutout.

Further objects are to provide a housed type of fused cut-out with latching mechanism that is so constructed that it will hold the door closed, allowing the door to be manually pulled open or pushed back to closed position, and which will provide a firmer or tighter latching hold when the fuse blows to offset any tendency for the door to blow open.

I It is well known that when an expulsion fuse blows, that there is a recoil of the fuse tube during the actual blowing of the fuse and this invention utilizes the force of such recoil and transmits such force, in part at least, to the latching mechanism to increase the hold of the latching mechanism during the actual blowing of the fuse.

This invention, therefore, has for its further object the provision of means which will latch the cut-out in closed position and will impose only a relatively slight strain on the fuse link, but which when the fuse blows, will automatically increase the pressure or grip of the latch means.

Further objects are to provide a novel form of contact structure and latching mechanism which are combined as a unitary assembly and insure adequate and yielding contact pressure and at the same time provide the automatic increase in the latching grip.

Further objects are to provide a novel form of housed type of fused cut-out in which the fuse tube assembly normally electrically joins the spaced stationary contacts, and in which such fuse tube assembly moves to open position, away from at least one of the stationary contacts, in which a novel form of combined stationary contact and latching means cooperates with the fuse tube assembly to assist or urge the fuse tube assembly to move towards open positionwhen the fuse tube assembly is released by the rupturing of the fuse link, but in which the latching hold or grip of the latching means is increased during the actual blowing of the fuse and yet in no way hinders the free opening movement of the fuse tube assembly after the fuse has blown.

Embodiments of the invention are shown in the accompanying drawings, in which:

Figure 1 is a vertical sectional view showing one form of the invention.

Figure 2 is a sectional view on the line 2-2 of Figure 1.

Figure 3 is a fragmentary view of the lower end of the fuse tube and guiding block showing the fuse link extracting member with parts broken away. 7

Figure 4 is a fragmentary view corresponding to Figure l and showing a further form of the invention.

Figure 5 is a fragmentary plan view of the upper contact support for the form of the invention shown in Figure 4.

Referring to Figures 1, 2 and 3, it will be seen that the cut-out comprises a housing I of porcelain or other suitable material provided with a door 2 of any suitable insulating material, such as a phenolic condensation product. The door is pivotally supported from the housing and may be provided with outwardly projecting trunnions or pivot pins 3 which may fit into hooklike members 4 carried by the housing and distinct and separate from the lower terminal 5, thereby providing for the ready removal of the door. The lower terminal member is provided with a pair of spring arms 6 which form contacts for gripping a metal block contact or sleeve member I, which latter is permanently secured to the door 2 as by means of screws 8. The metal block or sleeve 1 is provided with a tapered upper shoulder 9 which fits beneath a downwardly turned rigid arm or stop III which prevents inadvertent upward shifting of the door when the door is closed, thereby precluding the detaching of the trunnlons 3 from the hooks 4. See the dotted line showing at the lower portion of Figure 1.

The fuse may comprise a fuse tube ii provided with an upper contact cap l2 and with a lower metal sleeve ii. The lower cylindrical sleeve l3 slides within the contact block or sleeve 1, such 45 contact constituting a guide member or guide sleeve for slidably guiding the fuse tube. The metal sleeve l3 could be omitted, but by providing such metal sleeve, it provides metal sliding in metal, and warping or possible swelling of the tube could not prevent the free operation of the device. The metal sleeve It also provides a convenient means of carrying the stop. It is clear that the stop l8, or some other form of stop,

apin,couldbecarrieddirectlybythe the sleeve I! were omitted.

link extends from the upper contact through the open lower end of the fuse tube and preferably through a notched portion ll thereof andhasltslowerorfreeendsecuredbeneath the thumb nut I! to the contact block or guide member I.

Theupperend ofthefuselinkmaybeprovided with the fusible section it terminating in a head or button l'l clamped beneath the contact cap l2. the flexible leader extending downwardly and being indicated by the reference character It. Othertypesoffuselinkscouldbeemployed, though one of the standard forms has been illustrated.

Thelowercylindricalsleeve Ilofthefusetube is provided with laterally projecting shouldered members or pins It and these projecting members are located beneath a shouldered portion 2lofthecontactblockorguidelsothatupward recoil ofthefusetubemaybelimitedbyengagement of these two members. Obviously there maybeaslightupwardshiftofthedoorduring recoilwhichisiimitedbyengagcm ntofthe members I and II hereinbefore described.

A fuse link retracting and a fuse tube restraining member may be provided and may take the form of a springy looped wire member normally straddling the fuse tube and having supporting portions 2i which are positioned below the projecting members I! and may be provided with downwardly extending arms 22 normally located on opposite sides of the fuse tube and joined by a bail portion over which the portion ll of thefuselinkislooped. SeeFigurea land3.

The arms 2| are pivoted on the lower portion of the guide or block I by providing inturned portions on the arms and pivoting such portions in the block. It is also preferable to provide the block with some means to assist or urge the clockwise swinging of the restraining member. This may be readily accomplished by providing bevelled faces 23 which force the arms 2| apart slightly when the device is in the position shown in Figure l, the faces 23 tapering towards their lower ends.

Any other type of restraining means could be employed without departing from the spirit of this invention, provided the fuse tube is restrained by the fuse link as long as the fuse link is intact. This particular form of restraining means as shown herewith is more fully described and claimed in my copending application Serial Number 1,084 filed January 10, 1935, for Fuses.

If desired, outwardly projecting stops 24 may be integrally formed with the block or guide I to limit the outward swinging motion of the arms 2|.

From the description thus far given, it is obvious that when the fuse link is ruptured, the fuse withdrawing member rocks in a clockwise direction and withdraws the fuse link from the fuse tube and at the same time moves out of the way of the projecting portions ll of the fuse tube, thereby allowing the fuse time to slide downwardly and project outwfliy from the housing.

The upper terminal member is indicated at 25 and is provided with a contact carrying member secured thereto and provided with a pair of side arms 28, as shown in Figures 1 and 2, which may be bridged by a portion 21 integral therewith, as shown in Figure 1. This contact carrying member carries a pivot pin 20 upon which is pivoted the upper contact 2!. This contactflinrealityiscomposedofapairof sidearmsandanuppertransversememberil whichbridgeaacrossthesearmsandtowhich a flexible connector Ii is attached, the other end ofthe connectorbeing'securedto theupper terminal 2|. This upper contact 2! bears directly againsttheuppercontactcaplf ofthefusetube ii, as shown in Figure l.

A latch 82 is pivoted between the contact arms and turns downwardly over the front bevelled portion of the fuse cap l2, as shown in Figure 1. It is provided with a rearwardly projectingtongue It. Asprlng Ilislooselyeoiled about the pivot pin 20 and bears downwardly on the latch 32 and upwardly against the member 2lofthecontactsupport. Thisspringhasa double purpose. It not only presses the latch into latching position, but also urges the contact 2O downwardly into iirm engagement with the upper face of the fuse cap or upper contact i2 of the fuse. Due to the fact that the fuse cap I2 or upper contact is bevelled adjacent its upper end, it is obvious that the door can be pulled open against the yielding resistance of the latch 32. The bridge member 8| of the contact 20 is engaged by the tongue 33 of the latch when the fuse tube is out of contact with the upper contact member, as will hereinafter appear, and thus the latch is prevented from moving completely downwardly under the influence of the spring 84.

In the operation of the device, when an overload occurs and the fuse link is ruptured, the member 22 pulls any remaining portion of the leader out of the fuse tube and also rocks out of the way of the lugs it. The fuse tube then drops downwardly until the cap l2 rests upon the guide block 1. The door, however, remains closed as the contact arms 8, which are resilient, grip the guide block I and thus hold the door closed. The door may be rocked open and detached from the lower hooks and a new fuse link may be substituted for the one that has blown.

It is to be noted that the contact 29 is provided with an extension 35 which engages the bridge member 21 when the fuse has dropped to its inoperative position and thus prevents the contact 29 from rocking downwardly beyond a predetermined point.

when the fuse has been refused and the door repositioned, it can be rocked into circuit closing position as the upper contact l2 of the fuse tube will strike the pivoted upper contact 2. and will rock it into the position shown in Figure 1. During this closing motion. it is apparent that the latch 22, which is yieldingly'held, will be pressed upwardly and will yield and thereby prevent the placing of undue pressure on the fuse link due to the closing motion of the door.

It is apparent that when an expulsion fuse operates, the door is sometimes blown open due to gas pressure formed within the housing. However, this invention prevents the door from being blown open for as the fuse tube recoils upwardly, it rocks the upper contact 29 upwardly and thus increases the pressure that the spring 24 places on the latch 32, thus securing a firmer grip of the latch upon the upper end of the fuse tube, and as the fuse tube is attached to the door through the guide I, it is apparent that the door is held closed. The greater the recoil, the tighter the gripping of the latch will be.

On the other hand, it is apparent that the free downward sliding of the fuse tube is not hampered by the'latch as the upper end of the fuse tube or upper contact I! merely moves directly downwardly away from the latch and, in addition, the fuse tube is biased towards downward motion by the spring urged contact 29.

In the form of the invention shown in Figures 4 and 5 the same principle as that previously developed is employed. However, a different construction is used to accomplish these functions. In this form of the invention, the upper terminal 36 is provided with a contact support 31 which has the two arms connected by the bridge piece 38. This contact support carries a pivot pin 39 upon which the upper contact 40 is pivotally mounted. This upper contact is connected with the terminal member by means of the flexible leader 4|.

The contact member is provided with a pair of spaced arms 42 which are joined by a transverse portion or yoke 43. This yoke when the fuse tube has slid downwardly to its lowest position, strikes the inwardly projecting lugs or ears 44 which are integral with the arms 31 of the upper contact support, as most clearly shown in Figure 5. A spring 45 is loosely wrapped about the pivot pin 39 and bears against the member 38 and against the yoke 43 of the upper contact. A leaf spring 46 is carried by the yoke 43 of the upper contact and extends downwardly between the arms 42 of such upper contact and forwardly, terminating in an eye or rounded portion 41. This rounded portion bears against the bevelled :part of the upper contact cap I! of the fuse tube ll.

This form of the invention operates in the same manner as that previously described. The upward recoil of the fuse fube moves the upper contact 40 upwardly, as previously described, and this causes the portion 4'! of the leaf spring 48 to bear more heavily against the outer side of the cap I2 of the fuse tube, thereby preventing the door from being blown open, in identically the same manner as in the form first described. The latch member 46 in no way hinders the downward sliding motion of the fuse tube when the fuse link has been ruptured and the upper contact 40 presses downwardly on the fuse tube and biases the fuse tube towards open or inoperative position.

To refuse the device, the door is merely pulled open, as previously described, and a fresh fuse link inserted as this form of the invention is in all respects, other than that hereinabove described, identically like that of Figure 1. After the device has been refused, the door is rocked to closed position and it will be seen that in both forms of the invention the upper contact is in the path of movement of the upper portion of the fuse tube and consequently is rocked into its correct position as the door is closed.

However, the spring latch 46 yieldsas the door is pushed closed and does not put an undue pressure upon the fuse link due to the yielding hold that the latch has upon the fuse tube. Also the door may be pulled open as the latch will yield and allow the door to be opened, as in the first described form of. the invention.

In each form of the invention the usual eyelet or handle 48 may be provided on the door and if desired, the lower portion of the casing may be cut out to provide a channel to give clearance for the fuse tube, when the door is pulled open after the fuse has blown.

It will be seen that an automatically acting device has been provided which holds the door more tightly locked during the actual blowing of the fuse, and that this grip or hold of the device is increased due to the recoil of the fuse tube.

Also it will be seen that there is no hindrance offered the free sliding motion of the fuse tube towards inoperative position. The door may be manually opened or closed with the utmost facility whether the fuse has blow-n or not, as it is merely necessary to pull the door outwardly without any further operation,

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

I claim:

1. In a cut-out having recoil when it operates, the combination of a support, a member movable on recoil and movably mounted on said support and normally completing an electric circuit, latching means for yieldingly latching said member, said latching means having mechanism actuated by said recoil for increasing the hold of said latching means on said member.

2. In a fused cut-out the combination of a support having contacts, a fused member subject to recoil and normally electrically connecting said contacts, and latching means for said member for yieldingly latching said member in place. said latching means having mechanism actuated by said recoil for increasing the hold of said latching means while recoil persists.

3. In a cut-out, the combination of. a support having terminals, an expulsion fuse normally electrically connecting said terminals and including a fuse tube having a closed end and an open end, and latching means yieldingly engaging said fuse tube and including mechanism actuated by the recoil of said fuse tube for increasing the hold of said latching means during recoil, said latching means being released directly by said fuse tube when said fuse tube is pulled laterally from said latching means.

4. A housed cut-out having a housing, a door for said housing, a fuse tube mounted within said housing and subject to recoil when said cut-out blows, and latching means restraining the opening of said door, said latching means including mechanism actuated by said recoil for increasing the hold of said latching means.

5. A housed type of cut-out-comprising a housing, a door for said housing, a fuse unit located within said housing and attached to said door, said fuse unit being subject to recoil upon blowing, and latching means engaging said fuse unit and tending to hold said door closed, said latching means including mechanism actuated by the recoil of said fuse unit for increasing the hold of said latching means during the blowing of said fuse unit.

6. A housed type cut-out comprising a housing, a door for said housing, a fuse unit carried by said door, said fuse unit being subject to recoil upon blowing, an upper and a lower contact carried by said housing, said upper contact including a member displaced by the said fuse unit when said fuse unit recoils, and a latch for said fuse unit, said member urging said latch into firm engagement with said fuse unit while said member is displaced, said fuse unit having a fuse link nor-- mally electrically joining the upper and lower contacts of said housing.

'1. A housed type cut-out comprising a housing, a door for said housing, a fuse unit carried by said door, said fuse unit being subject to recoil upon blowing, an upper and a lower contact carried by said housing, said upper contact including a member displaced by the said fuse unit when said fuse unit recoils, and a latch for said fuse unit, said member urging said latch into firm engagement with said fuse unit while said member is displaced, said fuse unit having a fuse link normally electrically connecting the contacts of said housing, said fuse unit being movable with respect to said door and being released when said fuse link is ruptured.

8. A housed type of cut-out comprising a housing, a door for said housing, a fuse tube carried by said door, said fuse tube being subject to recoil upon blowing and having spaced contacts, upper and lower contacts carried by said housing, said fuse tube having a fuse link normally electrically connecting the contacts carried by said housing, said upper contact including a movable member displaced by said fuse tube when said fuse tube recoils, a latching member for holding said fuse tube against outward motion, and a spring urging said latching member towards latching position, said spring being tightened when said movable member is displaced upon recoil of said fuse tube.

9. A housed type of cut-out comprising a housing having upper and lower contacts, a door for said housing, a guide carried by said door, a fuse tube slidably guided by said guide and adapted to slide downwardly to inoperative position when said fuse blows, a fuse link normally electrically connecting the upper and lower contacts of said housing, means controlled by said fuse link for holding said fuse tube against sliding motion with respect to said door and released upon rupture of said fuse link, the upper contact of said housing including a lever engaging the upper end of said fuse tube, a latch carried by said lever, and spring means bearing against said latch and urging said latch into yielding latching engagement with said fuse tube, said lever being moved when said fuse tube recoils upon blowing of the fuse link and increasing the pressure exerted by said spring upon said latch.

10. A housed type of cut-out comprising a housing. having upper and lower contacts, a door for said housing, a guide carried by said door, a fuse tube slidably guided by said guide and adapted to slide downwardly to inoperative position when said fuse blows, a fuse link normallyelectrically connecting the upper and lower contacts of said housing, means controlled by said fuse link for holding said fuse tube against sliding motion with respect to said door and released upon rupture of said fuse link, the upper contact of said housing including a lever engaging the upper end of said fuse tube, alatch carried by said lever, and spring means bearing against said latch and urging said latch into yielding latching engagement with said fuse tube, said lever being moved when said fuse tube recoils upon blowing of the fuse link and increasing the pressure exerted by said spring upon said latch, said latch being yieldable when said door is manually pulled open and said fuse link is intact.

11. A housed cut-out having a housing provided with contacts, a door for said housing. an arcing tube subject to recoil and movably mounted with- 75 in said housing, a conductor within said tube normally electrically completing the circuit between the contacts of said housing, current responsive means for interrupting the circuit between said contacts, latching means restraining the opening of said door, and mechanism actuated by said re- 5 coil for increasing the hold of said latching means.

12. A housed cut-out having a housing provided with contacts, a door for said housing, an arcing tube subject to recoil and movably mounted within said housing, a conductor within said tube normally electrically completing the-circuit between the contacts of said housing. current responsive means for interrupting the circuit between said contacts and for releasing said arcing tube, latching means restraining the opening of said door, and mechanism actuated by said recoil for increasing the hold of said latching means.

13. A housed cut-out having a housing provided with contacts, a door for said housing, an arcing tube subject to recoil and movably mounted within said housing, an expulsible conductor within said tube normally electrically completing the circuit between the contacts of said housing, current responsive means for interrupting the circuit between said contacts and for releasing said arcing tube, latching means restraining the opening of said door, and mechanism actuated by said recoil for increasing the hold of said latching means.

14. A housed type of cut-out comprising a housing, a door for said housing, a cut-out unit located within said housing and movably carried by said door, said housing having spaced contacts, said cut-out unit normally electrically connecting said spaced contacts, one of the contacts of said housing having latching means yieldingly coacting with said cut-out to hold said cut-out normally in circuit closed position, said cut-out being laterally movable into circuit closing position and being longitudinally movable to circuit opening position.

15. A housed type of cut-out comprising a housing, a door for said housing, a cut-out unit located within said housing and subject to recoil, means guiding said cut-out unit for recoil mo- 41 tlon inwardly of said housing, latching means movably carried within said housing for restraining the opening of said door, and means moved by the recoil motion of said cut-out unit for increasing the hold of said latching means during st the recoil of said cut-out unit.

16. A housed type of cut-out comprising a housing, a door for said housing, a cut-out unit located within said housing and subject to recoil, means slidably guiding said cut-out unit for re- 54 coil motion inwardly of said housing, latching means movably carried within said housing for restraining the opening of said door, and means moved by the recoil motion of said cut-out unit for increasing the hold of said latching means q during the recoil of said cut-out unit.

17. A housed type of cut-cut comprising a housing, a door for said housing, a fuse tube mounted within said housing, guiding means for guiding said fuse tube inwardly of said housing 6 when said fuse tube recoils. a member located within said housing and mechanically moved upon recoil of said fuse tube, and a latch normally restraining said door against opening and being yieldingly held in latching position, and 1 means interposed between said member and said latch for increasing the yielding hold of said latch when said member is moved upon recoil of said fuse tube.

18. In a cut-out having recoil when it oper- 1 ates, the combination of a support, a member movable on recoil and movably mounted on said support and normally completing an electric circuit, latch means for yieldingly latching said member, said latch means having mechanism actuated by said recoil for increasing the hold of said latch means on said member, normally spaced means limiting the recoil of said member, and means normally holding said spaced means in spaced relation whereby said member is free to execute recoil movement.

19. A housed cut-out having a housing, a door for said housing, a fuse tube mounted within said housing and subject to recoil when said cut-out blows, latching means restraining the opening of said door, said latching means including mechanism actuated by said recoil for increasing the hold of said latching means, and means carried jointly by said door and said housing for limiting the upward motion of said door. 

